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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Designing and Evaluating Technologies for Virtual Reality Therapies that Promote Neuroplasticity

Kyryllo, Danica 18 March 2014 (has links)
Increasingly, virtual reality therapy (VRT) technologies are being used to augment pediatric rehabilitation. The mechanisms underlying success/failure of VRTs are not well understood. This thesis proposed an innovative 3-phase framework for evaluating VRT technologies with respect to neuroplasticity based on results of a scoping review of 21 studies. A case study was undertaken to demonstrate use of the framework to design and evaluate ‘Musical Steps’, a VRT technology aimed at promoting heel contact in toe-walking children. 5 therapists and 4 children were engaged in this study. The system accurately detected 88%(SD=7%) of heel contacts and was rated positively in usability testing (phase 1). Feasibility studies indicated that, while enjoyable, children did not understand the feedback provided and hence, heel contact was not increased (phase 2). These findings will direct future reiterations prior to evaluating clinical impact (phase 3). The proposed framework may enhance design and translation of therapeutically relevant VRTs.
22

Modelagem dos movimentos funcionais robótico-assistidos para a reabilitação dos membros superiores: redução dos graus de liberdade de um manipulador antropomórfico / Functional Movement Modeling for robot-assisted upper

ABADIA, Fernando Gonçalves 19 April 2010 (has links)
Made available in DSpace on 2014-07-29T15:08:24Z (GMT). No. of bitstreams: 1 Dissertacao - Fernando Goncalves Abadia.pdf: 2172647 bytes, checksum: 521c16d1c14b335efd25247e9a66c082 (MD5) Previous issue date: 2010-04-19 / Rehabilitation robotics involves the development of active devices for various processes in the health field. In the rehabilitation case, it replace the physical assistance by a robotic device, under the supervision of the therapist. According to some authors, there is much evidence that repetitive movements can help in the rehabilitation of stroke patients. Therefore, there is feasibility of building a low cost robotic manipulator of an anthropomorphic arm with few degrees of freedom in the rehabilitation of patients in early brain injury phase (muscle hypotony phase). The objective of the study outlined here is to determine, through simulation, the appropriate kinematic of an anthropomorphic robotic manipulator that best approximate the functional movements to be relearned by stroke patients. The kinemetry was the method used to measure the characteristics of these movements. The data acquisition was performed from three subjects who performed the movements of combing hair, drinking from cup, bring it to his mouth and waving, greeting movement. These data were compared with the direct and inverse kinematics of the simulated manipulator in MatLab environment. The results showed that, despite the limitations of movements, the simulated manipulator is feasible for rehabilitation of patients who are in the initial phase of stroke, with a low cost of implementation. / A reabilitação robótica é uma ciência que permite o desenvolvimento de dispositivos ativos para vários processos no campo da saúde. No caso da reabilitação, substitui a assistência física por um dispositivo robótico, sob a supervisão do terapeuta. Segundo alguns autores, há muitas evidências de que os movimentos repetitivos podem ajudar na reabilitação de pacientes vítimas de choques traumáticos ou de acidente vascular encefálico - AVE. Nesta perspectiva há viabilidade de se construir um manipulador robótico de um braço antropomórfico com poucos graus de liberdade na reabilitação dos pacientes na fase inicial do AVE (fase de hipotonia muscular) visando baixos custos. Neste aspecto, o objetivo do presente projeto é determinar, por meio de simulação, as apropriadas modelagens da cinemática de um manipulador robótico de um braço antropomórfico que melhor se aproximem dos movimentos funcionais a fim de serem reaprendidos pelos pacientes. A cinemetria foi o método utilizado para avaliar as características cinemáticas destes movimentos, a partir da coleta de dados realizada com uma amostra constituída por três sujeitos, que realizaram os movimentos de pentear os cabelos, pegar um copo e levá-lo à boca e acenar cumprimentando. Estes dados foram comparados à cinemática direta e inversa do manipulador simulado em ambiente MatLab. Os resultados mostraram que, apesar das limitações dos movimentos, o manipulador simulado é viável para reabilitação de pacientes que se encontram na fase inicial do AVE, apresentando um baixo custo de implementação.
23

Estudo e avaliação de técnicas de processamento do sinal mioelétrico para o controle de sistemas de reabilitação. / Study and evaluation of techniques for myoelectric signal processing to control rehabilitation systems.

Rodrigo Lício Ortolan 05 April 2002 (has links)
Este trabalho tem a finalidade de analisar algumas técnicas de processamento do sinal mioelétrico, de forma a possibilitar uma posterior implementação de um circuito, que reconheça este sinal e apresente como saída um sinal de controle a ser utilizado em sistemas de reabilitação. Foram simuladas e avaliadas três técnicas de filtragem para o sinal mioelétrico, a fim de atenuar a interferência dos principais ruídos que corrompem este sinal. As técnicas avaliadas foram: filtragem digital clássica; cancelamento de ruído adaptativo e reconstrução do sinal por meio das componentes obtidas pela transformada wavelet. Também foi implementado e analisado um sistema simplificado de reconhecimento dos padrões para este sinal, realizado por meio de uma rede neural artificial, em que foi aplicado em sua entrada o próprio sinal mioelétrico e não suas características obtidas por processamentos matemáticos. Diante dos resultados obtidos os canceladores de ruído adaptativos apresentaram melhores resultados com relação às outras técnicas de filtragem. Apesar de não ter sido adequada para a filtragem, a transformada wavelet mostrou-se uma poderosa ferramenta de análise de sinais, em virtude da sua característica multiresolução. A técnica utilizada para reconhecer os padrões do sinal mostrou bons resultados com os sinais analisados. / This work has the purpose to analyze some techniques for myoelectric signal processing, towards a subsequent implementation of a circuit which can recognize this signal and present as output a control signal to be used in rehabilitation systems. Simulation and evaluation of three filtering techniques for the myoelectric signal were done in order to attenuate the main interferences of noises which corrupt this signal. The evaluated techniques were: classic digital filtering; adaptive noise cancelling and the signal reconstruction through the obtained components by the wavelet transform. A simplified system of pattern recognition for this signal also was implemented and analyzed, accomplished through an artificial neural network. The myoelectric signal itself was applied to the input instead of its characteristics obtained by mathematical processing. According to the results obtained the adaptive noise cancelling presented better results in comparison to the other filtering techniques. Despite not being adequate for filtering, the wavelet transform proved to be a powerful tool for signal analysis, by virtue of its multiresolution characteristics. The technique used to recognize the signal patterns has shown good results with the analyzed signals.
24

Development of Learning Control Strategies for a Cable-Driven Device Assisting a Human Joint

Hao Xiong (7954217) 25 November 2019 (has links)
<div>There are millions of individuals in the world who currently experience limited mobility as a result of aging, stroke, injuries to the brain or spinal cord, and certain neurological diseases. Robotic Assistive Devices (RADs) have shown superiority in helping people with limited mobility by providing physical movement assistance. However, RADs currently existing on the market for people with limited mobility are still far from intelligent.</div><div><br></div><div>Learning control strategies are developed in this study to make a Cable-Driven Assistive Device (CDAD) intelligent in assisting a human joint (e.g., a knee joint, an ankle joint, or a wrist joint). CDADs are a type of RADs designed based on Cable-Driven Parallel Robots (CDPRs). A PID–FNN control strategy and DDPG-based strategies are proposed to allow a CDAD to learn physical human-robot interactions when controlling the pose of the human joint. Both pose-tracking and trajectory-tracking tasks are designed to evaluate the PID–FNN control strategy and the DDPG-based strategies through simulations. Simulations are conducted in the Gazebo simulator using an example CDAD with three degrees of freedom and four cables. Simulation results show that the proposed PID–FNN control strategy and DDPG-based strategies work in controlling a CDAD with proper learning.</div>
25

Command of a Virtual Neuroprosthesis-Arm with Noninvasive Field Potentials

Foldes, Stephen Thomas January 2010 (has links)
No description available.
26

Esforço do ombro na locomoção de pacientes paraplégicos: avaliação cinética e eletromiográfica / Shoulder effort in paraplegic locomotion: kinetics and EMG assessment

Ortolan, Rodrigo Lício 05 July 2007 (has links)
Pacientes lesados medulares frequentemente mencionam dores nos ombros, devido à elevada demanda dos membros superiores. Estes pacientes se submetem a diferentes tipos de reabilitação, no entanto é importante avaliar os métodos utilizados em tais programas para evitar possíveis prejuízos. O objetivo deste trabalho é avaliar o esforço e a atividade muscular dos ombros em pacientes paraplégicos caminhando com Estimulação Elétrica Neuro Muscular (EENM) e um andador em seções de reabilitação e comparar com duas atividades diárias executadas por estes indivíduos: propulsão da cadeira de rodas e elevação para alívio da pressão. Quinze homens adultos com paraplegia foram avaliados. Os movimentos em 3 dimensões foram obtidos com um sistema de 6 câmeras de infravermelho, e a atividade mioelétrica de 6 músculos dos ombros foi obtida bilateralmente por eletrodos de superfície ativos. Um andador instrumentalizado capturou a força durante a marcha, e a força nas outras duas atividades foi obtida por dinâmica inversa utilizando os dados cinemáticos e antropométricos. Os dados cinéticos e da atividade muscular foram avaliados estatisticamente utilizando análise de variância (ANOVA) e o teste das diferenças menos significativas de Tukey com nível de significância p<0,05. Foram obtidos picos de força quatro vezes maiores durante a marcha comparando-se à propulsão da cadeira de rodas. O esforço do ombro durante a marcha e a elevação foi equivalente, porém o lado direito durante a marcha apresentou maiores valores. O músculo mais ativo durante a marcha foi o tríceps, seguido pelo peitoral maior, deltóide anterior e trapézio inferior. A ação geral dos músculos durante a marcha também foi maior comparada aos outros exercícios executados. A marcha com EENM e andador, realizada por lesados medulares durante as seções de reabilitação, requer esforços significativos dos membros superiores, podendo gerar complicações nas articulações do ombro. Lesados medulares submetidos a seções de reabilitação que executam esforços significativos devem ser frequentemente monitorados, por métodos de ultra-som ou ressonância magnética, para evitar o comprometimento dos membros superiores e a consequente perda das funções de independência remanescentes / Spinal Cord Injured subjects often refer pain in their shoulders, due to the increased demand of the upper limbs. These subjects usually go through different rehabilitation strategies. Therefore, it becomes rather important to assess those methods in order to avoid further injuries to the patients. The goal of this work was to evaluate the shoulder effort and muscular activity in paraplegic subjects during gait with Neuromuscular Electrical Stimulation (NMES) with the aid of a walker and to compare it with two daily activities: wheelchair start up and weight relief raise. Fifteen adult male paraplegics were part of this study. The three-dimensional motions were acquired with six infrared cameras, and surface-active electrodes recorded the electromyography activity of 6 shoulder muscles, bilaterally. The vertical reaction force during walking was measured with a strain gauge instrumented walker, and the horizontal (wheelchair start-up) and vertical (weight relief raise) forces were obtained by inverse dynamics from kinematics and anthropometric data. The statistics of kinetic and electromyography data were done by analysis of variance (ANOVA) and the Tukey least significant differences post hoc test with significance level of p<0,05. Results have shown NMES gait force peaks being about four times higher than the values obtained for wheelchair start-up. The shoulder effort (force and torque) during walking and weight relief was similar, although the right side during NMES gait presented greater values. The triceps was the most active muscle during NMES walking, followed by pectoralis major, anterior deltoid and lower trapezius. The overall muscular activity during NMES walking was again higher than the other tasks executed. The NMES walking, when performed by spinal cord injured subjects can lead to injuries to the shoulder girdle. Due to the results obtained, continuous supervision of paraplegic upper limb effort should therefore be part of any rehabilitation center and for that ultrasound or magnetic resonance imaging may be recommended
27

Desenvolvimento do protótipo de uma prótese antropomórfica para membros superiores / Development of an anthropomorphic prosthesis prototype for superior members

Camargo, Daniel Rodrigues de 11 August 2008 (has links)
A finalidade desse trabalho é desenvolver um protótipo de uma prótese antropomórfica multifuncional para membros superiores para pacientes amputados. Seu objetivo é substituir a mão natural perdida, de forma a auxiliar a realização de algumas tarefas diárias do usuário. A prótese possuirá características antropomórficas, tais como aparência e movimentação semelhantes às da mão humana, e características naturais inerentes à mesma, por exemplo, o arco reflexo. Além disso, contará também com meios de realimentação táteis das informações de forças aplicadas pela prótese em objetos, bem como sua temperatura para o paciente, suprindo assim uma das carências das próteses convencionais. Esse dispositivo terá incorporado na sua construção sensores diversos para realizar as funções propostas e contará com um algoritmo baseado em redes neurais artificiais, capaz de identificar padrões dos sinais mioelétricos do paciente, que serão utilizados como sinais de controle, possibilitando ao paciente um comando natural. Todas essas implementações visam contribuir para a redução da taxa de rejeição de próteses para membros superiores e possibilitar uma maior reabilitação e reintegração do paciente à sociedade. / The purpose of this assignment is to develop a multifunctional and anthropomorphic upper limb prosthesis prototype for amputated patients. Its objective is to substitute the natural lost hand, in a way to improve the performance of regular activities. This prosthesis will have anthropomorphic characteristics, like appearance and movement, similar to the ones of the human hand, and natural characteristics inherent to it, for example the reflected arc. Another characteristic will be the tactile feedback ways of obtaining the information of the forces applied by the prosthesis in objects, as well as their temperature for the patient, overcoming therefore one of the traditional prosthesis\' deficiency. This device will have incorporated in its construction many sensors in order to do the proposed functions and it will use an algorithm based on the artificial neural network that is able to recognize patterns of myoelectric signals of the patient, which will be used as control signals, making possible to the patient a natural command. All of these implementations objective to contribute for the reduction of the rejection rate of prostheses for upper limb members and make possible a better rehabilitation and reintegration of the patient in the society.
28

Design and Evaluation of Pressure-based Sensors for Mechanomyography: an Investigation of Chamber Geometry and Motion Artifact

Posatskiy, Alex 19 December 2011 (has links)
Mechanomyography (MMG) has been proposed as a control modality for alternative access technologies for individuals with disabilities. However, MMG recordings are highly susceptible to contamination from limb movements. Pressure-based transducers are touted to be the most robust to external movement although there is some debate about their optimal chamber geometry, in terms of low frequency gain and spectral flatness. To investigate the question of preferred geometry, transducers with varying chamber shapes were designed, manufactured and tested. The best performance was achieved with a transducer consisting of a low-frequency MEMS microphone, a 4 micron thick aluminized mylar membrane and a rigid conical chamber 7 mm in diameter and 5 mm in height. Furthermore, microphone-derived MMG spectra were found to be less influenced by motion artifact than corresponding accelerometer-derived spectra. However, artifact harmonics were present in both spectra, suggesting that bandpass filtering may not remove artifact influences permeating into MMG frequency bands.
29

Design and Evaluation of Pressure-based Sensors for Mechanomyography: an Investigation of Chamber Geometry and Motion Artifact

Posatskiy, Alex 19 December 2011 (has links)
Mechanomyography (MMG) has been proposed as a control modality for alternative access technologies for individuals with disabilities. However, MMG recordings are highly susceptible to contamination from limb movements. Pressure-based transducers are touted to be the most robust to external movement although there is some debate about their optimal chamber geometry, in terms of low frequency gain and spectral flatness. To investigate the question of preferred geometry, transducers with varying chamber shapes were designed, manufactured and tested. The best performance was achieved with a transducer consisting of a low-frequency MEMS microphone, a 4 micron thick aluminized mylar membrane and a rigid conical chamber 7 mm in diameter and 5 mm in height. Furthermore, microphone-derived MMG spectra were found to be less influenced by motion artifact than corresponding accelerometer-derived spectra. However, artifact harmonics were present in both spectra, suggesting that bandpass filtering may not remove artifact influences permeating into MMG frequency bands.
30

Desenvolvimento do protótipo de uma prótese antropomórfica para membros superiores / Development of an anthropomorphic prosthesis prototype for superior members

Daniel Rodrigues de Camargo 11 August 2008 (has links)
A finalidade desse trabalho é desenvolver um protótipo de uma prótese antropomórfica multifuncional para membros superiores para pacientes amputados. Seu objetivo é substituir a mão natural perdida, de forma a auxiliar a realização de algumas tarefas diárias do usuário. A prótese possuirá características antropomórficas, tais como aparência e movimentação semelhantes às da mão humana, e características naturais inerentes à mesma, por exemplo, o arco reflexo. Além disso, contará também com meios de realimentação táteis das informações de forças aplicadas pela prótese em objetos, bem como sua temperatura para o paciente, suprindo assim uma das carências das próteses convencionais. Esse dispositivo terá incorporado na sua construção sensores diversos para realizar as funções propostas e contará com um algoritmo baseado em redes neurais artificiais, capaz de identificar padrões dos sinais mioelétricos do paciente, que serão utilizados como sinais de controle, possibilitando ao paciente um comando natural. Todas essas implementações visam contribuir para a redução da taxa de rejeição de próteses para membros superiores e possibilitar uma maior reabilitação e reintegração do paciente à sociedade. / The purpose of this assignment is to develop a multifunctional and anthropomorphic upper limb prosthesis prototype for amputated patients. Its objective is to substitute the natural lost hand, in a way to improve the performance of regular activities. This prosthesis will have anthropomorphic characteristics, like appearance and movement, similar to the ones of the human hand, and natural characteristics inherent to it, for example the reflected arc. Another characteristic will be the tactile feedback ways of obtaining the information of the forces applied by the prosthesis in objects, as well as their temperature for the patient, overcoming therefore one of the traditional prosthesis\' deficiency. This device will have incorporated in its construction many sensors in order to do the proposed functions and it will use an algorithm based on the artificial neural network that is able to recognize patterns of myoelectric signals of the patient, which will be used as control signals, making possible to the patient a natural command. All of these implementations objective to contribute for the reduction of the rejection rate of prostheses for upper limb members and make possible a better rehabilitation and reintegration of the patient in the society.

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